The invention relates in general to an electric switching device, particularly a circuit breaker, having a contact system including a movable contact bridge and at least two stationary contact parts spaced apart one from the other and cooperating with the bridge to close or open an electric circuit.
Switching devices of this kind find wide application in practice and are mass-produced. They are employed for performing a great variety of switching operations and are activated either manually or by driving mechanism or by solenoids. The switching devices of this kind contain at least one contact system of which the individual contact points are designed either as contact breakers or makers, depending upon the desired switching application. In practice it is frequently desired, for example when a large number of switching devices are needed for the construction of program control systems, that a contact breaker be converted into a contact maker, or vice versa, particularly when a change is to be made in the programmed control or if other switching tasks are desired.
In order to make such a change in the switching circuit, it has been hitherto necessary to deactivate the entire switching system and dismount the switching devices in question from a switching board or a switching panel, for example. Such disassembly requires loosening of all connection conduits whereupon the switching device is disassembled and converted from a circuit breaker into a circuit maker, or vice versa. The reinstallation proceeds in reverse order. Known are switching devices in which one or more contact bridges are installed at different levels in a bridge carrier, the levels being adjustable in dependence on whether a circuit breaker or maker is intended for a particular use. It is true that in such devices it is possible to remove a housing cover without a complete dismounting of the device from the system, and then remove the contact bridge carrier from the device, and change the level arrangement of the contact bridges according to changed conditions, and then reinstall the adjusted bridge carrier into the device. Nonetheless, all these converting operations in prior-art switching devices ae both complicated and, in any event, very time-consuming and troublesome and can be performed only by specialized service men who known the construction of the device in detail.